Vector Clarke Transform
Collaboration diagram for Vector Clarke Transform: ## Functions

static __INLINE void arm_clarke_f32 (float32_t Ia, float32_t Ib, float32_t *pIalpha, float32_t *pIbeta)
Floating-point Clarke transform. More...

static __INLINE void arm_clarke_q31 (q31_t Ia, q31_t Ib, q31_t *pIalpha, q31_t *pIbeta)
Clarke transform for Q31 version. More...

## Detailed Description

Forward Clarke transform converts the instantaneous stator phases into a two-coordinate time invariant vector. Generally the Clarke transform uses three-phase currents `Ia, Ib and Ic` to calculate currents in the two-phase orthogonal stator axis `Ialpha` and `Ibeta`. When `Ialpha` is superposed with `Ia` as shown in the figure below Stator current space vector and its components in (a,b).

and `Ia + Ib + Ic = 0`, in this condition `Ialpha` and `Ibeta` can be calculated using only `Ia` and `Ib`.

The function operates on a single sample of data and each call to the function returns the processed output. The library provides separate functions for Q31 and floating-point data types.

Algorithm where `Ia` and `Ib` are the instantaneous stator phases and `pIalpha` and `pIbeta` are the two coordinates of time invariant vector.
Fixed-Point Behavior
Care must be taken when using the Q31 version of the Clarke transform. In particular, the overflow and saturation behavior of the accumulator used must be considered. Refer to the function specific documentation below for usage guidelines.

## ◆ arm_clarke_f32()

 static __INLINE void arm_clarke_f32 ( float32_t Ia, float32_t Ib, float32_t * pIalpha, float32_t * pIbeta )
static

Floating-point Clarke transform.

Parameters
 [in] Ia input three-phase coordinate `a` [in] Ib input three-phase coordinate `b` [out] *pIalpha points to output two-phase orthogonal vector axis alpha [out] *pIbeta points to output two-phase orthogonal vector axis beta
Returns
none.

Definition at line 5290 of file arm_math.h.

## ◆ arm_clarke_q31()

 static __INLINE void arm_clarke_q31 ( q31_t Ia, q31_t Ib, q31_t * pIalpha, q31_t * pIbeta )
static

Clarke transform for Q31 version.

Parameters
 [in] Ia input three-phase coordinate `a` [in] Ib input three-phase coordinate `b` [out] *pIalpha points to output two-phase orthogonal vector axis alpha [out] *pIbeta points to output two-phase orthogonal vector axis beta
Returns
none.

Scaling and Overflow Behavior:

The function is implemented using an internal 32-bit accumulator. The accumulator maintains 1.31 format by truncating lower 31 bits of the intermediate multiplication in 2.62 format. There is saturation on the addition, hence there is no risk of overflow.

Definition at line 5320 of file arm_math.h.

inertial_sense_ros
Author(s):
autogenerated on Sun Feb 28 2021 03:18:01